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Hydraulic clutch masters and slaves

Discussion in 'Manual Transmission & Clutch' started by Dale A, Apr 1, 2020.

  1. Dale A

    Dale A Junior Member

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    Truck Year:
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    R 3500
    Engine Size:
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    Anyone aware of the relationship between the volume of fluid pushed by the master and what the slave requires for a proper operation when depressing the clutch peddle?
     
  2. nvrenuf

    nvrenuf Full Access Member

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    Why? Are you using a different reservoir?
     
  3. bluex

    bluex Full Access Member

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    Bore size x travel length should give you required fluid volume of both.
     
  4. Dale A

    Dale A Junior Member

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    John, I have install a ZF6 in place of the sm465. I now have a different slave than factory but still have the factory master in the truck, that being a 91 crew 2wd with a 454.
     
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  5. Dale A

    Dale A Junior Member

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    Bluex, I did some math this morning. I do happen to have a brand new 03 master cylinder that I bought cause I thought the original one was bad. Also was struggling with 91' and 03' hose connectors. Well the 03 master is very different than the 91 in how it mounts in the truck so I replaced the original 91' model, with a new unit. In completing the math, figured out the 03' master pumps almost twice the volume of fluid that the 91' master pumps. By the way, 03' is the year of the ZF6. it came out of an 03' C 3500 Silverado. So it looks like its back to the R and D of making the 03' master fit the firewall of a 91 square body. And the push rod and the reservoir.:superhack:
     
  6. davisw73

    davisw73 Junior Member

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    Truck Year:
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    I am having this same problem right now. I have an 85 C20 with NV4500. The master is stock 87 and the trans is a 99 with internal slave. The square body master doesn't seem to have enough volume to completely release the clutch. I can see it pushing the throw-out bearing and I can even get a feeler gauge between it but it's not pushing it down far enough to completely disengage.
    I have been looking at some Wilwood masters with a bigger bore, but they all only seem to have a 1" stroke and I don't want to have to move the pivot point on the pedal if I don't have to. Today after work I am going to try and get some volume numbers. Has anyone figured out the best way to mount a newer master yet? I can fab something up, but would rather find something that will bolt up.
     
  7. SquareRoot

    SquareRoot Full Access Member

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    I'm converting my 85K20 from auto to NV4500 right now. Mine uses OEM external slave so it matches the factory master cylinder dimensions.

    You need to contact Advanced Adapters. They sell a conversion kit for the 4500 that uses either the (early) external slave or the (later) internal bearing. Find out what they use in their kit.
     
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  8. SquareRoot

    SquareRoot Full Access Member

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    http://www.novak-adapt.com/knowledge/clutches-etc

    This explains it well. It mentions Jeep several times but its referring to Chevy conversions into Jeeps.
     

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